@article{03769944,
title = {Spectral inequalities involving the sums and products of functions.},
journal = {International Journal of Mathematics and Mathematical Sciences},
volume = {5},
year = {1982},
pages = {141-157},
doi = {10.1155/S0161171282000143},
zbl = {0489.26010},
language = {en},
url = {http://dml.mathdoc.fr/item/03769944}
}
Chong, Kong-Ming. Spectral inequalities involving the sums and products of functions.. International Journal of Mathematics and Mathematical Sciences, Tome 5 (1982) pp. 141-157. doi : 10.1155/S0161171282000143. http://gdmltest.u-ga.fr/item/03769944/